I don't have any immediately at hand, so whether you believe some random guy on the internet from here on out on is up to you.

I actually did a little bit of private investigation myself into betting markets of a handful of sports a number of years ago out of both curiosity, and potentially profit. And I'm currently working on perceptions of skill and merit along various systems just for my own intellectual project.

I find it interesting you've discovered the systematic bias strategy of choosing your opponents and events (these are done both consciously by players in various systems, but often formally and informally supported or enabled by various governing bodies and competitive structures).

Aside from both the boredom (arbitraging and scraping stats can be meticulously dull especially in fields you have no interest in or if you lack a hustler or profit maximising mentality or significant bankroll), opportunity cost (how much you can earn in other markets with such skills given equal investment of time and safety), the moral question (you're taking money from other ignorant bettors and I personally consider a lot of gambling and exploitation of people's ignorance relatively immoral, the house/market maker in many contexts still profits just through sheer trading frequency or other profit making actions), these days you have many market makers targeting little sharps presumably because they want to keep their ignorant base happy and gambling and don't want the perception of playing agaist certain losses or against people capable of seeing through the systems to reveal internal operations.

That's the only reason I can come up with for why they target and close accounts of profitable gamblers while they're still taking the house edge on every bet as profit.

What I (of course) also informally discovered in some markets I looked into was evidence of various fixing activities and systemic biases.

Now if you were going to do this for large scale profit, one of the things you are going to have to do is stop the illusion you're modelling skill and start modelling corruption.

It's all well and good for these articles to come out and pretend skilled prediction will win you millions, but you can be the best statistician in the house and if you place bets in a game based on models of skill, but the game outcome is rigged, you can kiss goodbye to your bankroll.

Criminals win because their outcomes aren't statistical or based on skill.

And now you're suddenly in the business of modelling and fighting people who profit from rigging markets rather than morally neutral statistical models in games of skill.

You can of course model such and go down that rabbit hole, but at some point you either buy into such a world and get involved (either by being hired by or interacting with criminal and questionable enterprise) or you are effectively trying to do statistical surveillance of criminal activities... Which will then show up in the statistical patterns of your own betting activities and potentially alert said enterprises to your existence.

And that's about where I bowed out of my investigations and turned back to more theoretical work.

That's not particularly a world I want to be involved in, but I am relatively confident popular sports and markets have illicit match fixing and other activities going on in them at significant levels, but I'm not interested in fighting with or building implicit knowledge bases of people who have million dollar anonymous backers from Vegas, billion dollar contracts, and whom die from accidental sleeping pill overdoses... If you know what I mean ...